Advice Needed On Recapping Power Amp

I agree that it is very unlikely that you actually need caps replaced at this point, but if you are after a modification that would help. I can see that. I have replaced power supply caps on a few amps with very good results.  
4 things that you need to seek is lowest ESR possible and highest capacitance that will physically fit along with voltage of at least that of the rails of the amp and high enough temperature rating.  
Most supply caps are 85 degree parts.  That should be absolutely fine... If you had a pure class A amplifier, then maybe move up to 105 degree parts,  but 85 degree typically sound great and work well. 
If you have say a typical 10,000 mfd supply cap at 85 degrees and 63volt part.  Look for the highest value capacitance that will fit that meet that 85 degrees and 63 volts(or higher)  
I just replaced the power supply caps in my old Sumo Nine.  It had 85 degree 10,000 mfd 63 volt parts.  Because it is pure class A, I moved to 105 degree parts and found 22,000 mfd, 80volt parts that would fit that ended up having very much lower esr than even the Panasonic caps that I put in there back in the late 80's.  

For any Electrolytics on the circuit board.  Those circuits often would have very much different results change the values,  so other that raising the voltage try to keep the exact values of the caps that you are replacing and all will be fine. 
But again,  none of this should be a NEED for your amplifier. 

Hi   @kosst_amojan    ....  Well, I guess that really depends quite a bit about your transformer first. My knowledge is limited about "Inrush" current.  
To those reading these comments.. In-rush current is the current flow into a product when you flip on the power switch.  It can be quite large.  That is why on some of these old beast of an amplifier, you see the lights dim when you fire them up. 
I am not a indepth as some others, but as I understand it,  the larger the transformer, especially in toroid types are more susceptible in passing current. When caps are idle,  they look like a dead short,  So the VERY IMPORTANT part here is.... The Low esr along with natural wire resistance is the only filter for this current (unless there is a soft start circuit)... I have done this to maybe 5 or 6 amplifiers.  NEVER had an issue.  Each time, the amp sounded better, but I yield to opinions of those in the know. 

Kijanki,
    I've never claimed to be the sharpest tool in the shed, but as said above, I've done this many times. I have only had positive results.  How do propose that you get parasitic inductance introduced in a properly designed power supply?  The only issue that I can see is a poor excuse of rectifier. As long as you bridge is rated for the current you should be fine and An ideal cap has zero inductance or resistance on its own. 

@rlb61     after all of this, I'm sure that you'll decide not to recap, but as we have all state, not really needed at this point. 

Well, I guess that I'm a garage operator.... I have always made sure that my rectifiers would handle the current, other than that, I've always increased capacitance without fear.  This is the 3rd time that I've worked on my Sumo, a couple of times ago, I replaced its rectifiers. This time I took it to a friends house and  I increased the power supply my self. He has the amp now finishing up a few mods and repairs from a lightening strike. I consider my old friend to be one of the best old school audio engineers ever. He is not as well known as some, but I've been with him rubbing shoulders with some of the best and trust him implicitly.   

@kijanki     Not to be argumentative, this is more for me to be informed. First, I've never added capacitance to a switching supply and This is just not how I understand inductance in relation to a power supply cap. 
Inductance would be creating a magnetic field, yet As the capacitor charges, the magnetic field does not remain static. This results in electromagnetic waves which radiate energy away. So the magnetic field dissipates. The cap itself is not inductive. 
So, I can see faulty, weak or under rated rectifiers.  Maybe if you flipped the switch at the exact instance when your ac was hitting its peak in the sine wave. 
Again,  I've done this a bunch.... The first time was in 1980.  Parasound built a chipped amp around a Sanken STK084... I called Dick Schram and he sent me 2 circuit boards, I ended up using an STK086, put higher grade parts in it.  His amp had 4 - 6800 mfd caps in it.  I used a separate supply case with 12 - 6800mfd caps.  That was my first foray into increasing capacitance and wow, what a difference that it made. 

and yes, I understand the 120hz "primitive unregulated switcher"  is not a switching supply. Sorry if I added confusion.

Well Kijanki,  If you ever need advice in the speaker world, I understand that world  thoroughly.  As far as amps, I'll just stay in the garage.  I've enjoyed doing the few repairs and mods that I've done and to date, I've never damaged anything. So life goes on. I don't call him often for help, but if I ever need him, I've got a guru that is one of my best friends to call on.  All is good in the world.